PRETORIA, South Africa (AP) -- Oscar Pistorius refused to look at a photo of his dead girlfriend's bloody head wounds while testifying at his murder trial Wednesday as the prosecutor urged the star athlete to "take responsibility" for killing her.
"It's time that you look at it," chief prosecutor Gerrie Nel said, setting the stage for a rigorous first day of cross-examination of Pistorius, the double-amputee Olympian charged with premeditated murder for shooting Reeva Steenkamp three times through a toilet door at his home.
"I remember," Pistorius said of Steenkamp's bloodied head, becoming distraught and then crying as he turned away from the gruesome image of the injuries he inflicted that were displayed next to him in a packed courtroom in South Africa's capital.
Nel said Steenkamp's head "exploded" when it was struck by one of four hollow-point bullets that Pistorius fired through the door on Feb. 14, 2013 with his 9 mm pistol. The showing of the photograph on TV screens in the courtroom caused gasps among spectators, who included Steenkamp's mother, June. The police photo showed a side view of the dead model and reality TV star's head, with a mass of blood and human tissue on the back and upper parts. Her eyes were closed.
"I will not look at a picture where I'm tormented by what I saw and felt that night," Pistorius said. "As I picked Reeva up, my fingers touched her head. I remember. I don't have to look at a picture, I was there."
Pistorius, 27, says he shot Steenkamp in the pre-dawn hours on Valentine's Day - in the head, arm and hip - by mistake thinking she was a dangerous intruder behind the door in his bathroom about to come out and attack him. Prosecutors charge he killed the 29-year-old intentionally, and Nel aggressively questioned Pistorius for the first time.
"You killed her," Nel said. "You shot and killed her," and he asked Pistorius to say it. Pistorius would not, saying merely: "I did."
Pistorius faces a possible prison term of 25 years to life if convicted of premeditated murder.
Nel also showed a video, first broadcast by Sky News days before the trial started, of the celebrated athlete firing a gun at a watermelon at a shooting range. On the video, Pistorius can be heard saying the melon was "softer than brains" after it explodes when the bullet hits it, and calling the powerful .50-caliber handgun he was using a "zombie stopper."
Referring to the watermelon, Nel said to Pistorius: "You know the same happened to Reeva's head. It exploded."
Defense lawyer Barry Roux objected to the gun video being shown, saying it was inadmissible character evidence and amounted to a legal "ambush" of the defense.
After the dramatic start, prosecutor Nel also started to poke holes in details of Pistorius' version of the events of the fatal night. The champion runner said that his claim in a court document a year ago that he went out onto a balcony at his home before the shooting was incorrect. Pistorius said he went to the edge of the balcony but not outside. The discrepancy could be significant because Pistorius says he heard a noise in the bathroom that alerted him to a possible intruder, which would have been harder if he was out on the balcony.
Nel tried to pin down Pistorius on whether he meant to fire into the toilet cubicle door at a perceived intruder, or whether his gun discharged accidentally. Pistorius said he didn't intend to shoot "anyone" and that he fired "before thinking" because he thought his life was in danger, prompting Nel to accuse him of weighing the legal implications of the question before answering.
The dogged prosecutor implied that Pistorius, who grew more agitated, was becoming emotional because he was faced with a difficult question. The judge noted that Pistorius had been emotional throughout the trial.
Pistorius told his questioner that he was trying to be careful with his answers because the stakes were high.
"My life is on the line," he said. Nel retorted: "Reeva doesn't have a life anymore because of what you've done."
And Nel tried to dismantle a sympathetic image of Pistorius that the defense had sought to build up in three days of testimony, asking the athlete to explicitly acknowledge that he killed Steenkamp.
"I made a mistake," Pistorius said.
"What was your mistake?" Nel shot back.
Pistorius then said he "took Reeva's life."
Nel also questioned the defense's portrayal of Pistorius as a good role model. The prosecution depicts him as an angry hothead with a gun obsession.
The prosecutor asked Pistorius if people looked up to him as a sporting hero, if he would hide anything and if he lived by Christian principles.
"I'm here to tell the truth, I'm here to tell the truth as much as I can remember," Pistorius said. He also said: "I'm human. I have sins."
Torchia reported from Johannesburg.